Sidewalk Fossils

Lab Activities

Simulating fossils: There are many plans for this type of activity.
They range from the most rudimentary to the very realistic and
elaborate. Summarized from many sources, here are some
suggestions. Each will need to be adjusted to suit the ability
and level of the students as well as the available time and equipment.

1. Layer various grades of sand in a box, inserting "fossils" in some
layers. Have students record their findings as they carefully
excavate. This can be used to illustrate the principles of
stratigraphy (oldest layers, and fossils, on the bottom and newer
layers on top).

2. Students press shells, etc. into wet plaster of Paris, or
modeling clay, to demonstrate the formation of mold fossils.

3. After making a mold (#2), cover the mold with a separating
layer of dry powder, or petroleum jelly. Pour a layer of
plaster of Paris on top. When dry, the layers should separate
giving you both mold and cast fossils.

4. Persuade a small animal, such as a mouse, lizard, or whatever
you might have in your lab, to walk across a smoothed layer of fine
sand. Pour plaster of Paris over the tracks. When dry, the
plaster can be separated from the sand to show a cast of the "fossil"
tracks.

5. Making epoxy mold "paper weights" with insects included can be
used to illustrate the formation insect fossils embedded in amber.

6. Using a stream table, demonstrate that floods deposit course
layers (sand), between floods silt (mud) layers are deposited. At
the same time "fossils" can be dropped into some of the layers.